Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Braz. j. biol ; 83: 1-6, 2023. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468830

RESUMO

Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.


Os morcegos apresentam grande importância na homeostasia dos ecossistemas e são hospedeiros de uma rica diversidade de micro-organismos como bactérias, vírus e fungos com potencial patogênico. Portanto, este estudo visou isolar fungos presentes em amostras biológicas de morcegos na cidade de Sinop - MT, que possui grandes áreas de desmatamento devido à urbanização e agricultura. Foram capturados 48 morcegos de diferentes espécies, em onze fragmentos florestais urbanos definidos de acordo com fluxo de pessoas e animais domésticos, para obtenção de amostras biológicas. Essas amostras foram processadas e submetidas aos cultivos microbiológicos, para isolamento e identificação dos gêneros dos fungos. Dos 48 morcegos, 34 (70,83%) foram positivos para pelos menos um gênero de fungo, sendo 18 (37,5%) fêmeas e 16 (33,33%) machos, e os gêneros isolados a partir das amostras biológicas foram Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp. e Candida sp., que podem ser causadores de infecções oportunistas. Desse total, a espécie que apresentou maior positividade para pelo menos um gênero de fungo foi Molossus molossus com 21 (43,8%). Nossos resultados demonstram que os morcegos capturados nos fragmentos florestais urbanos na cidade de Sinop - MT, podem atuar como agentes veiculadores de fungos com potencial patogênico, aumentando assim o risco de exposição e aquisição de infecções fúngicas oportunistas por pessoas e animais domésticos.


Assuntos
Animais , Fungos/patogenicidade , Quirópteros/microbiologia , Quirópteros/sangue , Alternaria , Aspergillus , Candida , Cryptococcus , Fusarium , Penicillium , Scopulariopsis , Trichosporon
2.
J Wildl Dis ; 57(1): 242-245, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33635999

RESUMO

We determined venous blood gas, acid-base, and biochemical parameters for thirteen free-ranging Indian flying foxes (Pteropus giganteus) in Myanmar, using a handheld i-STAT analyzer with CG8+ and CHEM8 cartridges. For field-based projects, portable blood analyzers enable identification and management of electrolyte and acid-base imbalances and collection of physiologic data, but present logistical challenges.


Assuntos
Análise Química do Sangue/veterinária , Gasometria/veterinária , Quirópteros/sangue , Animais , Análise Química do Sangue/instrumentação , Gasometria/instrumentação , Testes Hematológicos/veterinária , Mianmar , Sistemas Automatizados de Assistência Junto ao Leito
3.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 57(3): e168582, 2020. mapas, tab, graf
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1122183

RESUMO

It was provide a hematological profile of Artibeus lituratus (Phyllostomidae: Stenodermatinae). Animals were collected from October 2017 to February 2018 in an urban forest in the city of Rio de Janeiro, Southeastern Brazil. Males and females showed similar overall mean values for the parameters analyzed. Males had higher values for erythrocytes (RBC), hematocrit and basophils. Females had higher levels of eosinophils than males. The hematological values reported here will serve as reference for future research on health conditions of free-living and captive populations of Artibeus lituratus, as well as for research on pathogens associated with these bats.(AU)


O presente trabalho estabeleceu o perfil hematológico de morcegos frugívoros de vida livre, A. lituratus (Phyllostomidae: Stenodermatinae). As amostragens foram realizadas de outubro de 2017 a fevereiro de 2018 em uma floresta urbana na cidade do Rio de Janeiro, Sudeste do Brasil. Machos e fêmeas apresentaram valores médios gerais semelhantes para os parâmetros analisados. Os machos apresentaram valores de eritrócitos (RBC), hematócrito e basófilos mais altos. As fêmeas apresentaram níveis mais elevados de eosinófilos que os machos. Os valores hematológicos aqui reportados servirão de referência para pesquisas sobre condições de saúde de populações de Artibeus lituratus em vida livre e de cativeiro, assim como para pesquisas sobre patógenos associados a esses morcegos.(AU)


Assuntos
Animais , Quirópteros/sangue , Eosinófilos , Eritrócitos , Hematócrito , Testes Hematológicos/veterinária
5.
Gen Comp Endocrinol ; 262: 1-11, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29474936

RESUMO

The aim of the present study was to evaluate the mechanism by which embryonic development in Cynopterus sphinx is impaired during the period of increased accumulation of white adipose tissue during winter scarcity of food. The change in the mass of white adipose tissue during adipogenesis showed significant positive correlation with the circulating glucose level. But increase in circulating glucose level during the adipogenesis showed negative correlation with circulating progesterone and adiponectin levels. The in vivo study showed increased glucose uptake by the adipose tissue during adipogenesis due to increased expression of insulin receptor (IR) and glucose transporter (GLUT) 4 proteins. This study showed decline in the adiponectin level during fat accumulation. In the in vitro study, ovary treated with high doses of glucose showed impaired progesterone synthesis. This is due to decreased glucose uptake mediated decrease in the expression of luteinizing hormone-receptor, steroidogenic acute regulatory protein, IR, GLUT4 and AdipoR1 proteins. But the ovary treated with adiponectin either alone or with higher concentration of glucose showed improvement in progesterone synthesis due to increased expression of IR, GLUT4 and AdipoR1 mediated increased glucose uptake. In conclusion, increased circulating glucose level prior to winter dormancy preferably transported to white adipose tissue for fat accumulation diverting glucose away from the ovary. Consequently the decreased availability of adiponectin and glucose to the ovary and utero-embryonic unit may be responsible for impaired progesterone synthesis and delayed embryonic development. The delayed embryonic development in Cynopterus sphinx may have evolved, in part, as a mechanism to prevent pregnancy loss during the period of decreased energy availability.


Assuntos
Adiponectina/sangue , Adiposidade , Glicemia/metabolismo , Quirópteros/embriologia , Quirópteros/metabolismo , Desenvolvimento Embrionário , Ovário/metabolismo , Esteroides/biossíntese , Tecido Adiposo Branco/metabolismo , Animais , Quirópteros/sangue , Feminino , Transportador de Glucose Tipo 4/metabolismo , Fosfoproteínas/metabolismo , Progesterona/metabolismo , Receptor de Insulina/metabolismo , Receptores de Adiponectina/metabolismo , Receptores do LH/metabolismo , Transdução de Sinais
6.
Emerg Infect Dis ; 24(1): 114-117, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29260678

RESUMO

To determine whether fruit bats in Singapore have been exposed to filoviruses, we screened 409 serum samples from bats of 3 species by using a multiplex assay that detects antibodies against filoviruses. Positive samples reacted with glycoproteins from Bundibugyo, Ebola, and Sudan viruses, indicating filovirus circulation among bats in Southeast Asia.


Assuntos
Quirópteros/sangue , Quirópteros/virologia , Ebolavirus , Marburgvirus , Proteínas do Envelope Viral/sangue , Animais , Glicoproteínas/sangue , Glicoproteínas/genética , Glicoproteínas/isolamento & purificação , Estudos Soroepidemiológicos , Singapura/epidemiologia
7.
Acta amaz ; 47(4): 365-368, Oct.-Dec. 2017. map, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455344

RESUMO

ABSTRACT Amblypygids are among the main predators in the ferriferous caves in Carajás National Forest, state of Pará (Amazon region of Brazil). One of the most common amblypygid species in this region is Heterophrynus longicornis (Butler 1873), and its most frequent prey are crickets of the family Phalangopsidae, which are abundant in the caves of Pará. Because they are primarily predators, necrophagy by amblypygids is not frequent in nature, and there are only two literature records of necrophagy of bats by Amblypygi. On December 11th, 2013, we observed an individual H. longicornis eating a bat carcass in a Pará ferriferous cave. The amblypygid exhibited considerable interest in the bats carcass, and it did not interrupt its meal even when lamps or a cameras flash were pointed in its direction. The availability of nutrients in the carcass must promote this opportunistic behavior in caves, especially considering the habitual scarcity of trophic resources in underground environments when compared to epigean environments.


RESUMO Amblipígios são considerados um dos principais predadores em cavernas de litologia ferrífera localizadas na Floresta Nacional de Carajás no estado do Pará (região da Amazônia brasileira). Uma das espécies de amblipígios mais comuns nesta região é Heterophrynus longicornis (Butler 1873), e uma das presas mais frequentes são grilos da família Phalangopsidae, abundantes nas cavernas do Pará. Por serem predadores, a necrofagia em amblipígeos foi pouco observada na natureza, sendo que existem dois registros na literatura sobre necrofagia de morcegos por amblipígios. Em 11 de dezembro de 2013, observamos um H. longicornis se alimentando da carcaça de um morcego em uma caverna de litologia ferrífera da Floresta Nacional de Carajás. Aparentemente, havia um interesse considerável pela carcaça do morcego por parte do amblipígio, uma vez que o indivíduo não interrompeu sua alimentação, mesmo quando iluminado por lanternas e o flash da câmera. A abundância de nutrientes na carcaça deve favorecer este comportamento oportunístico em cavernas, especialmente quando se considera a habitual escassez de recursos tróficos destes ambientes subterrâneos, quando comparados a ambientes epígeos.


Assuntos
Animais , Cadeia Alimentar , Quirópteros/metabolismo , Quirópteros/sangue
8.
Gen Comp Endocrinol ; 248: 27-39, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28412388

RESUMO

The aim of this study was to evaluate the role of prolactin as a modulator of luteal steroidogenesis during the period of delayed embryonic development in Cynopterus sphinx. A marked decline in circulating prolactin levels was noted during the months of November through December coinciding with the period of decreased serum progesterone and delayed embryonic development. The seasonal changes in serum prolactin levels correlated positively with circulating progesterone (P) level, but inversely with circulating melatonin level during first pregnancy showing delayed development in Cynopterus sphinx. The results also showed decreased expression of prolactin receptor-short form (PRL-RS) both in the corpus luteum and in the utero-embryonic unit during the period of delayed embryonic development. Bats treated in vivo with prolactin during the period of delayed development showed significant increase in serum progesterone and estradiol levels together with significant increase in the expression of PRL-RS, luteinizing hormone receptor (LH-R), steroidogenic acute receptor protein (STAR) and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) in the ovary. Prolactin stimulated ovarian angiogenesis (vascular endothelial growth factor) and cell survival (B-cell lymphoma 2) in vivo. Significant increases in ovarian progesterone production and the expression of prolactin-receptor, LH-R, STAR and 3ß-HSD proteins were noted following the exposure of LH or prolactin in vitro during the delayed period. In conclusion, short-day associated increased melatonin level may be responsible for decreased prolactin release during November-December. The decline in prolactin level might play a role in suppressing P and estradiol-17ß (E2) estradiol levels thereby causing delayed embryonic development in C. sphinx.


Assuntos
Quirópteros/embriologia , Quirópteros/metabolismo , Corpo Lúteo/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Prolactina/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Quirópteros/sangue , Colesterol/sangue , Corpo Lúteo/efeitos dos fármacos , Estradiol/sangue , Feminino , Hormônio Luteinizante/metabolismo , Melatonina/sangue , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Progesterona/sangue , Prolactina/sangue , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores da Prolactina/metabolismo , Ovinos , Útero/efeitos dos fármacos , Útero/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
BMC Genomics ; 17(1): 906, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27832764

RESUMO

BACKGROUND: Chiroptera, the bats, are the only order of mammals capable of true self-powered flight. Bats exhibit a number of other exceptional traits such as echolocation, viral tolerance and, perhaps most puzzlingly, extreme longevity given their body size. Little is known about the molecular mechanisms driving their extended longevity particularly at the levels of gene expression and post-transcriptional regulation. To elucidate the molecular mechanisms that may underlie their unusual longevity, we have deep sequenced 246.5 million small RNA reads from whole blood of the long-lived greater mouse-eared bats, Myotis myotis, and conducted a series of genome-wide comparative analyses between bat and non-bat mammals (human, pig and cow) in both blood miRNomes and transcriptomes, for the first time. RESULTS: We identified 539 miRNA gene candidates from bats, of which 468 unique mature miRNA were obtained. More than half of these miRNA (65.1 %) were regarded as bat-specific, regulating genes involved in the immune, ageing and tumorigenesis pathways. We have also developed a stringent pipeline for genome-wide miRNome comparisons across species, and identified 37 orthologous miRNA groups shared with bat, human, pig and cow, 6 of which were differentially expressed. For bats, 3 out of 4 up-regulated miRNA (miR-101-3p, miR-16-5p, miR-143-3p) likely function as tumor suppressors against various kinds of cancers, while one down-regulated miRNA (miR-221-5p) acts as a tumorigenesis promoter in human breast and pancreatic cancers. Additionally, a genome-wide comparison of mRNA transcriptomes across species also revealed specific gene expression patterns in bats. 127 up-regulated genes were enriched mainly in mitotic cell cycle and DNA repair mechanisms, while 364 down-regulated genes were involved primarily in mitochondrial activity. CONCLUSIONS: Our comprehensive and integrative analyses revealed bat-specific and differentially expressed miRNA and mRNA that function in key longevity pathways, producing a distinct bat gene expression pattern. For the first time, we show that bats may possess unique regulatory mechanisms for resisting tumorigenesis, repairing cellular damage and preventing oxidative stresses, all of which likely contribute to the extraordinary lifespan of Myotis myotis.


Assuntos
Quirópteros/sangue , Quirópteros/genética , Longevidade/genética , MicroRNAs/sangue , MicroRNAs/genética , Animais , Análise por Conglomerados , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Ontologia Genética , Genes Supressores de Tumor , Humanos , Transcriptoma
10.
Rev. Inst. Med. Trop. Säo Paulo ; 57(6): 497-503, Nov.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-770116

RESUMO

The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.


Os surtos de raiva em humanos transmitida por Desmodus rotundus em 2004 e 2005 no nordeste do estado do Pará, Brasil, Amazônia Oriental, fizeram desta uma área prioritária para estudos sobre essa zoonose. Diante disso, o presente estudo fornece dados sobre esse fenômeno em contexto urbano, afim de avaliar uma possível circulação do vírus clássico da raiva (RABV) entre espécies de morcegos em Capanema, cidade localizada na bacia Amazônica. Os morcegos foram coletados em 2011, com auxílio de redes de espera durante as estações seca e chuvosa. Amostras de encéfalo e de sangue foram coletadas para o diagnóstico virológico e sorológico, respectivamente. Das 153 amostras de encéfalo analisadas, nenhuma encontrou-se positiva para infecção pelo RABV, porém, 50,34% (95% CI: 45,67-55,01) das amostras de soro analisadas estavam soropositivas. Artibeus planirostris foi a espécie mais comum, e seu percentual de indivíduos soropositivos foi bem elevado (52.46%, 95% CI: 52,31-52,60). Porções estatisticamente iguais de soropositivos foram registrados nas estações (c2 = 0,057, d.f. = 1, p = 0,88). Uma porção significativamente elevada de machos (55,96%, 95% CI: 48,96%-62,96%), e adultos (52,37%, 95% CI: 47,35%-57,39%) foram soropositivos. Apesar de nenhuma das amostras de encéfalo terem sido positivas para raiva, a alta proporção de espécimes soropositivos indica uma possível circulação do RABV nessa área urbana.


Assuntos
Animais , Anticorpos Antivirais/sangue , Quirópteros/virologia , Vírus da Raiva/imunologia , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Saúde da População Urbana , Brasil , Encéfalo/virologia , Distribuição de Qui-Quadrado , Quirópteros/sangue , Cidades/estatística & dados numéricos , Vetores de Doenças , Raiva/sangue , Raiva/diagnóstico , Estações do Ano , Estudos Soroepidemiológicos , Fatores Sexuais
11.
Gen Comp Endocrinol ; 208: 73-84, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25241398

RESUMO

The bat Scotophilus heathi exhibit prolonged anovulatory condition known as delayed ovulation coinciding with the period of extensive fat accumulation. The present study was undertaken to find out whether extensive accumulation of fat in S. heathi is responsible for suppression of ovarian activity by increasing production of adipokine resistin in the bat. This was achieved by (a) investigating variation in serum resistin level in relation to the changes in the body fat mass and (b) evaluating the effect of resistin treatment on ovarian activity with reference to steroid synthesis. An attempt was also made to determine whether resistin mediate its effects on ovary through signal transducer and activator of transcription 3 (STAT3) signaling mechanism. The results showed significant seasonal variation in serum resistin level with the peak level coinciding with the period of maximum fat accumulation, high circulating androgen level and period of anovulation. The treatment with resistin to the bat caused increase in androstenedione due to stimulatory effects on 3ß-hydroxysteroid dehydrogenase, but decrease in estradiol level due to inhibitory effect on aromatase. Resistin treatment increased androgen receptor protein together with increased insulin receptor but not through conventional luteinizing hormone receptor and steroidogenic acute regulatory protein mediated pathways. This study further showed that resistin treatment increases androstenedione synthesis and up-regulates insulin receptor in the ovary through STAT3 mediated pathways. These findings suggest that obese women through increased resistin synthesis may causes development of non-ovulatory antral follicles through insulin receptor signaling cascade.


Assuntos
Quirópteros/crescimento & desenvolvimento , Quirópteros/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Resistina/farmacologia , Esteroides/sangue , Adiponectina/sangue , Adiposidade/efeitos dos fármacos , Androstenodiona/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quirópteros/sangue , Estradiol/metabolismo , Feminino , Humanos , Insulina/sangue , Leptina/sangue , Hormônio Luteinizante/sangue , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Progesterona/metabolismo , Receptores de Superfície Celular/metabolismo , Reprodutibilidade dos Testes , Resistina/sangue , Esteroides/biossíntese
12.
Naturwissenschaften ; 101(4): 285-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24515336

RESUMO

Oxidative stress--an imbalance between reactive pro- and neutralising antioxidants--damages cell structures and impairs fitness-relevant traits such as longevity and reproduction. Theory predicts that feeding on diets with high antioxidant content such as fruits should reduce oxidative stress; however, there is no support of this idea in free-ranging mammals. Bats cover a large variety of ecological niches, and therefore, we asked if measures of oxidative stress are lower in species with fruit diets. We measured reactive oxygen metabolites (ROM) representing total pro-oxidants produced and antioxidants in the plasma of 33 Neotropical bat species. Species with a fruit diet showed the lowest level of ROM and the highest concentration of antioxidants, followed by omnivorous and animalivorous species. Potentially, frugivorous species ingest more antioxidants with food and thus are able to neutralise more pro-oxidants than species not feeding on fruits, resulting in an overall lower level of oxidative stress. We therefore showed for the first time that measures of oxidative stress vary according to diets in free-ranging mammals.


Assuntos
Quirópteros/fisiologia , Dieta , Frutas , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/análise , Quirópteros/sangue , Espécies Reativas de Oxigênio
13.
Arq. bras. med. vet. zootec ; 62(2): 343-349, abr. 2010. tab, ilus
Artigo em Português | LILACS | ID: lil-551834

RESUMO

Caracterizou-se filogeneticamente o vírus da raiva, isolado de morcegos hematógafos (Demodus rotundus). Cento e noventa e nove D. rotundus foram capturados em cinco abrigos, no Norte e Noroeste do Estado do Rio de Janeiro e sul do Espírito Santo. Sete deles foram positivos para a raiva. Amostras desses vírus foram sequenciadas e comparadas com sequências provenientes de diversos estados brasileiros. As sequências de vírus da raiva isoladas, na região norte do Estado do Rio de Janeiro, mostraram características que as distinguem de amostras de vírus isoladas em outras regiões do país, no entanto foram idênticas às isoladas de bovinos no noroeste do Rio de Janeiro.


Rabies samples isolated from vampire bats captured in the Rio de Janeiro State were phylogenetically analyzed. One hundred and ninety nine vampire bats were captured from five shelters from North and Northwest of Rio de Janeiro and South of Espírito Santo States. Seven of them were positive for rabies. Theses samples were sequenced and compared with rabies virus sequences from several Brazilian states. The sequences of rabies virus, isolated in the present work, from North of Rio de Janeiro State, showed characteristics that differ of the sequences isolated from bats from other Brazilian regions. However, they were identical to samples isolated from cattle in Northwest of Rio de Janeiro state.


Assuntos
Animais , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/patogenicidade , Filogenia , Quirópteros/anatomia & histologia , Quirópteros/sangue
14.
Reproduction ; 138(6): 935-44, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19690096

RESUMO

The aim of the present study was to evaluate the seasonal variation in serum melatonin levels and their relationship to the changes in the serum progesterone level, ovarian steroidogenesis, and embryonic development during two successive pregnancies of Cynopterus sphinx. Circulating melatonin concentrations showed two peaks; one coincided with the period of low progesterone synthesis and delayed embryonic development, whereas the second peak coincided with regressing corpus luteum. This finding suggests that increased serum melatonin level during November-December may be responsible for delayed embryonic development by suppressing progesterone synthesis. The study showed increased melatonin receptors (MTNR1A and MTNR1B) in the corpus luteum and in the utero-embryonic unit during the period of delayed embryonic development. The in vitro study showed that a high dose of melatonin suppressed progesterone synthesis, whereas a lower dose of melatonin increased progesterone synthesis by the ovary. The effects of melatonin on ovarian steroidogenesis are mediated through changes in the expression of peripheral-type benzodiazepine receptor, P450 side chain cleavage enzyme, and LH receptor proteins. This study further showed a suppressive impact of melatonin on the progesterone receptor (PGR) in the utero-embryonic unit; this effect might contribute to delayed embryonic development in C. sphinx. The results of the present study thus suggest that a high circulating melatonin level has a dual contribution in retarding embryonic development in C. sphinx by impairing progesterone synthesis as well as by inhibiting progesterone action by reducing expression of PGR in the utero-embryonic unit.


Assuntos
Quirópteros/embriologia , Desenvolvimento Embrionário , Melatonina/fisiologia , Animais , Células Cultivadas , Quirópteros/sangue , Quirópteros/metabolismo , Ritmo Circadiano/fisiologia , Embrião de Mamíferos , Desenvolvimento Embrionário/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hormônios Esteroides Gonadais/biossíntese , Melatonina/sangue , Melatonina/metabolismo , Melatonina/farmacologia , Gravidez , Progesterona/sangue , Receptores de Melatonina/metabolismo , Receptores de Melatonina/fisiologia
15.
J Zoo Wildl Med ; 36(2): 212-21, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17323561

RESUMO

This study evaluated the relationship between blood iron parameters and hepatic iron concentrations, and correlation of histologic findings with hepatic iron concentrations in a captive population of Egyptian fruit bats (Rousettus aegyptiacus) and island flying foxes (Pteropus hypomelanus). Blood samples were collected for complete blood counts, plasma biochemical profiles, serum iron concentrations, total iron-binding capacity, whole-blood lead concentrations, and plasma ferritin assays. Liver samples obtained by laparotomy were divided, with one half processed for histologic examination and the other half frozen and submitted for tissue mineral analysis. The histologic sections were scored by two blinded observers for iron deposition, necrosis, and fibrosis. The Egyptian fruit bats had significantly higher liver iron (mean = 3,669 +/- 1,823 ppm) and lead (mean = 8.9 +/- 5.8 ppm) concentrations than the island flying foxes (mean [Fe] = 174 +/- 173 ppm, mean [Pb] = 1.9 +/- 0.5 ppm). Hepatic iron concentrations significantly correlated with tissue lead concentrations, histologic grading for iron and necrosis, serum iron, transferrin saturation, and plasma ferritin (P < 0.001). Blood lead concentrations negatively correlated with tissue lead concentrations (P < 0.001). When the product of transferrin saturation and serum iron was greater than 51, an individual animal had a high probability of having iron overload. When the product of these two variables was greater than 90, there was a high probability that the animal had hemochromatosis. On the basis of this study, it appears that evaluation of serum iron, transferrin saturation, and plasma ferritin are useful and noninvasive methods for diagnosis of hemochromatosis in Egyptian fruit bats.


Assuntos
Quirópteros , Ferritinas/sangue , Hemocromatose/veterinária , Ferro/sangue , Fígado/metabolismo , Animais , Animais de Zoológico , Análise Química do Sangue/veterinária , Quirópteros/sangue , Quirópteros/metabolismo , Diagnóstico Diferencial , Feminino , Hemocromatose/diagnóstico , Hemocromatose/epidemiologia , Fígado/química , Masculino
16.
J Virol Methods ; 121(2): 259-61, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15381364

RESUMO

A monoclonal antibody (MAb) based solid-phase blocking ELISA was developed for detection of antibodies to Nipah virus. The ELISA was designed to detect remaining antigens on the plate with anti-Nipah MAb conjugate after the reaction with sample serum, and enabled simple procedure, detection of neutralizing antibody to Nipah virus, and application of samples from different animal species. Forty of 200 swine reference sera examined were positive by the ELISA, of which thirty seven were found positive by serum neutralization test. Sera from a total of 131 fruit bats captured in Malaysia were also tested and all found negative by the both tests. It is considered that the solid-phase blocking ELISA can be used as a screening test for Nipah virus infection followed by the serum neutralization test as confirmatory test.


Assuntos
Anticorpos Antivirais/sangue , Quirópteros/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Vírus Nipah/isolamento & purificação , Suínos/sangue , Animais , Anticorpos Monoclonais , Antígenos Virais , Bovinos , Ensaio de Imunoadsorção Enzimática/normas , Infecções por Henipavirus/sangue , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/veterinária , Humanos , Malásia/epidemiologia , Programas de Rastreamento/métodos , Testes de Neutralização/normas , Vírus Nipah/imunologia
17.
J Reprod Fertil ; 108(2): 171-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9038773

RESUMO

The fertility and viability of spermatozoa stored by male and female Gould's wattled bats, Chalinolobus gouldii, was investigated in a captive colony of ten bats (three males and seven females). Bats were housed in outdoor flight cages. Plasma progesterone concentrations, measured using double antibody radioimmunoassay, isolation experiments plus sperm motility and sperm membrane stability tests were used to evaluate the viability and fertility of stored spermatozoa. Mean plasma progesterone concentrations were lowest during midwinter (< 0.5 ng ml-1) with a 20-fold increase recorded in late winter to early spring. During pregnancy, plasma progesterone concentrations increased to about 13 ng ml-1 and returned to basal values soon after parturition. The results of the plasma progesterone assays and the isolation experiments indicate that female C. gouldii can store fertile spermatozoa for at least 33 days. The investigation of spermatozoa stored by male C. gouldii revealed that 6-7 months after peak spermatogenesis about 60% of the stored spermatozoa were motile and more than 60% had stable membranes, indicating that the spermatozoa stored by males were viable and likely to be fertile. The results of this study clearly indicate that both male and female C. gouldii are capable of storing fertile spermatozoa for prolonged periods.


Assuntos
Quirópteros/fisiologia , Fertilidade/fisiologia , Progesterona/sangue , Transporte Espermático , Espermatozoides/fisiologia , Animais , Sobrevivência Celular , Quirópteros/sangue , Feminino , Masculino , Gravidez , Estações do Ano , Fatores de Tempo
18.
Biol Chem Hoppe Seyler ; 376(10): 603-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8590629

RESUMO

The hemoglobin of the lobe-lipped bat (Chalinolobus morio, Vespertilionidae) is composed of 45% HbI and 55% HbII. Both components show identical alpha-chains but differ at the following three positions of their beta-chains: beta I/beta II 21: Glu/Asp, 70: Ser/Ala, and 135: Gln/Leu. High performance liquid chromatography revealed pure alpha-chains and a mixture of only partly separated beta-chains. Based on this material, the primary structures of all three globin chains could be achieved by automatic Edman degradation of the whole chains and peptides obtained by trypsin hydrolysis. Compared to human hemoglobin, Chalinolobus shows 17 replacements in the alpha-chains and 24/22 in the beta-chains. A sequence comparison of the globin chains from the three vespertilionid bats Chalinolobus morio and Myotis velifer (Vespertilioninae) as well as Antrozous pallidus (Nyctophilinae) supports a close relationship of the former only for the beta-chains. Molecular modeling showed that the replacements involved in three alpha 1/beta 1 and one alpha 1/beta 2 subunit interface contacts do not cause any interruption. All phosphate binding sites and amino acid residues responsible for the Bohr effect are unchanged. Thus normal physiological properties should be expected for Chalinolobus morio hemoglobin.


Assuntos
Quirópteros/sangue , Hemoglobinas/química , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Eletroforese das Proteínas Sanguíneas , Eletroforese em Gel de Poliacrilamida , Eritrócitos/química , Globinas/análise , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/análise
19.
Reprod Fertil Dev ; 7(5): 1163-76, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8848584

RESUMO

Blood was collected from breeding-season and pregnant P. poliocephalus females shot in the wild and from captive pregnant and ovariectomized P. poliocephalus and P. scapulatus females. Peripheral plasma progesterone concentrations measured by radioimmunoassay were similar to those obtained by gas chromatography-mass spectroscopy: in intact non-pregnant P. poliocephalus females without corpora lutea (CLs) values ranged from 2 to 30 ng mL-1; after ovariectomy, they ranged from 1 to 85 ng mL-1. A significant source of progesterone in these bats may be the adrenal. In P. poliocephalus, peripheral plasma progesterone concentrations showed relatively little change over the breeding season or in early pregnancy when a CL formed, but increased from mid pregnancy to reach 200-800 ng mL-1 in late pregnancy. A mid-pregnancy ovary with CL contained 2.80 ng progesterone whereas the contralateral ovary contained 0.13 ng. Overall, CL size decreased during pregnancy and was negatively correlated with plasma progesterone concentrations. In late pregnancy, the main source of progesterone appears to be the placenta; plasma concentrations increase with placental growth and are significantly correlated with placental weight, and placentas contain 4-8 micrograms progesterone g-1. There was no evidence that progesterone concentrations fall before parturition. Limited observations indicated that peripheral progesterone concentrations follow similar patterns in P. scapulatus.


Assuntos
Quirópteros/sangue , Prenhez/sangue , Progesterona/sangue , Animais , Corpo Lúteo/anatomia & histologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Ovariectomia , Placenta/metabolismo , Gravidez , Progesterona/biossíntese , Radioimunoensaio , Estações do Ano , Fatores de Tempo
20.
Rev. peru. med. trop ; 6: 45-9, 1992. tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-121514

RESUMO

Se realizó el estudio bacteriológico y serológico en 26 especínenes de Desmodus rotundus(Geoffroy Saint Hilaire), capturados en la localidad de Shansha, Huaráz-Ancash, a fin de determinar el posible rol de reservorios de Leptospiras de la especie Leptospira interrogans. Observaciones diresctas de tejido renal y hepático al microscópio de campo oscuro, mostraron la presencia de Leptospira en 6(23.07 por ciento)especímenes. Se detectaron anticuerpos contra Leptospira mediante la reacción de aglutinación microscópica (RAM)en 5(19.23 por ciento)vampiros investigados frente a L. javanica, L. pyrogenes, L. andamana y L. grippotyphosa. Del total de cultivos realizados, se aisló una cepa de Leptospira a partir del cultivo de hígado. Por los resultados obtenidos, se evidencia el rol de reservorios de Leptospira en este grupo de mamiferos, estudiados por primera vez en Perú. Se recomienda la investigación de un número mayor de especímenes, así como en otras especies de Chirópteros, principalmente para intentar el aislamiento de Leptospira y determinar la acción de los vampiros en la transmisión de esta espiroqueta al humano y animales domésticos


Assuntos
Animais , Leptospirose/diagnóstico , Quirópteros/classificação , Peru , Zoonoses/classificação , Zoonoses/etiologia , Zoonoses/microbiologia , Zoonoses/transmissão , Leptospira/isolamento & purificação , Leptospira/análise , Leptospira/classificação , Leptospira/patogenicidade , Leptospira interrogans/isolamento & purificação , Leptospira interrogans/patogenicidade , Leptospirose/classificação , Leptospirose/etiologia , Leptospirose/patologia , Leptospirose/sangue , Quirópteros/imunologia , Quirópteros/microbiologia , Quirópteros/urina , Quirópteros/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA